P11D is a form used by employers in the UK to report certain types of expenses and benefits provided to their employees. The form is used to report items that are not included in an employee's salary, such as company cars, health insurance, and other benefits in kind.

The purpose of the P11D form is to ensure that the value of these benefits is included in the employee's taxable income, and that the appropriate amount of income tax and National Insurance contributions are paid by the employee and the employer.

Employers are required to complete a separate P11D form for each employee who has received expenses or benefits during the tax year. The deadline for submitting P11D forms to HM Revenue and Customs (HMRC) is July 6th following the end of the tax year.

In addition to completing the P11D form, employers are also required to provide each employee with a copy of their P11D by July 6th. This enables employees to understand the value of the benefits they have received and how this affects their tax liability.

Overall, the P11D form is an important tool for ensuring that the correct amount of income tax and National Insurance contributions are paid by both employers and employees in relation to benefits in kind provided as part of an employment package.